Electrical boxes are commonly used to provide electrical service at convenient locations within buildings. The electrical boxes are commonly formed of plastic or metal and are usually securely fastened by screws or nails to the framework within the building. In newly constructed buildings, the open face of the electrical box, in which an electrical device such as an outlet or switch will be mounted, is usually flush with the surface of the wall or ceiling in which it is installed.
When existing buildings are renovated or restored, it is common for renovators to lay down new sheet stock such as sheet rock, paneling, etc., over the existing ceilings or walls. This causes the existing electrical boxes to become recessed within the wall by the thickness of the new sheet stock.
To solve this problem, box extenders of several different types have been developed. One type relies on a friction fit to hold the box extender in the existing electrical box. This extender has the disadvantage of not providing a secure attachment to the existing box, and the electrical device may slide further within the box making it hard to reach.
Another type of extender consists of an extension having walls of approximately the same configuration as the existing box and of fixed thickness. The extender is available in several thicknesses to accommodate several different sheet stock thicknesses. Although there are many thicknesses available, the extender sometimes is not of a proper thickness to bring the existing box flush with the new surface, and this creates an aesthetically undesirable appearance.
Another type of extender includes a body portion having at least one wall and open faces and a second open face. The extender includes side flanges having holes that align with brackets that are connected to the electrical box. This extender is difficult to use and install as brackets must be firmly attached to the electrical box and then two screws are used to attach each flange of the extender to the electrical box.
A supplemental part which is a variation of the electrical box extender can be used as a device insulator in those locations where an electrical device does not need to be extended to a new wall surface but rather where there is a limited amount of space to create a secure device which is not prone to shorting out. A typical example would be the installation of a GFCI device in an electrical box. The GFCI device is a bulky device that fits with little clearance into an electrical box. The terminals on the side of a GFCI are close fitting to the side of the metal electrical box and frequently the GFCI will be tripped when the terminals contact the side of the box. The supplemental part is inserted within an existing electrical box to act as a device insulator and keep bulky electrical devices insulated from the surrounding electrical box.
As described by these several limitations, extenders and supplemental parts of the present art have not proven fully satisfactory for extending electrical boxes flush with the new walls or ceilings in a renovated or restored building.